The invention relates to a beam position sensing apparatus for sensing position of ultraviolet (UV, DUV, EUV) beams.
Numerous medical, industrial and other processes rely on proper positioning of beams such as ultraviolet and deep ultraviolet beams and the like. Accurate positioning of the beams in such processes is critical.
Position sensing members such as quad cells, lateral effect detectors and the like are known. However, long-term exposure of such position sensing members to UV, DUV and EUV radiation results in rapid and serious degradation of performance of the position sensing member.
It is clear that the need remains for an apparatus for sensing position of ultraviolet, deep ultraviolet and the like beams wherein performance does not rapidly decline.
It is therefore the object of the present invention to provide such an apparatus.
Other objects and advantages of the present invention will appear hereinbelow.
In accordance with the present invention, the foregoing objects and advantages have been readily attained.
According to the invention, a position sensor for ultraviolet beams is provided, which comprises a beam positioning member for directing an ultraviolet beam along a path; a downconverter member for converting the beam to visible light; and a position sensing member for sensing position of the visible light thereon; and relay optics for directing the visible light to the position sensing member; wherein the position sensing member is communicated with the beam positioning member for conveying information regarding position of the visible light to the beam positioning member.